On the eighteenth wedding anniversary, the couple needs to do some extra work in order to make their day a big success and interesting. Therefore, they need to do a lot of work as this is a happy day for them. Here are 18th wedding anniversary wishes for sister that you can easily send to your sister to make her feel as special as she is.

18th Wedding Anniversary Wishes For Sister

1. I love you so much. You are my best friend and I can’t wait to spend your next 18 years with you. I wish you joy, happiness and a very healthy heart. May you both have many more years of happy marriage! Happy 18th wedding anniversary sister!
2. I love you, and happy anniversary. These parties just keep getting better! Can’t wait for the next one with you. Be safe on your trip and we’ll talk when you get back. Love ya, sis!
3. Dear Sister, you are my best friend and an amazing wife who makes me very happy. You always make me feel loved, happy and secure. I wish you a great life and wish the best for the future. Love you always!
4. HAPPY WEDDING ANNIVERSARY TO YOU!!!!!You both are the most wonderful people I’ve ever met. I’m so proud to call you my sister and your husband my brother. I truly hope you enjoy the rest of your day! May God continue to bless you both for years to come.
5. We’ve been together for 18 years, my sister. 18 years of laughter, fun and tears. You were there for me when I needed advice about the man I was dating, when my children were born, when I needed to talk about things, when our parent’s passed away. You are my rock and best friend and although you are 7 years older than me, we share an unbreakable bond. Thank you for always loving and supporting me. Through thick and thin! Happy 18th wedding anniversary sister!
6. I just wanted to let you know how proud I am of the woman that you have become. I love to see how strong your marriage is and how much joy you and Joe bring each other. You were two young kids when we went with you to pick out the ring, but you picked well. I couldn’t be happier for the two of you, full of love and bliss. Here’s to another 18 years!
7. Happy 18th wedding anniversary sister! I wanted to let you know how much i appreciate everything you do. Your support and love mean so much to me. You have always been there for me and I thank God every day that he brought you into my life! And I have no better friend in the whole world then you! I love you very much!
8. Though the years have passed, you are still as beautiful and kind as ever. I’m so happy you are my sister. I feel like you’re the only one who truly knows me. All I have to do is look at you and I know everything will be okay. Happy 18th wedding anniversary sister!
9. I know I’m not the best sister, but you are always there for me. You have always had my back and I couldn’t be more thankful for that. I love you more than words can say and I am so proud to call you my sister! Happy 18th wedding anniversary sister!
10. Happy 18th wedding anniversary sister! I’m really happy you found her honey. You two were always so perfect together and it seems nothing has changed. I know how hard it must be without a mom, so she will be a true Godsend to you. I can’t wait to meet her, you will show her the picture I am sure. I hope she is everything you want in a wife and mother to our nephews and niece. Love you sweetie!
11. Caring, Supportive, good listener. I love you, Sis. Happy 18th wedding anniversary sister!
12. Dear Sister it’s hard to believe that its been 18 years since you said yes to my brother. I love you so much and want to thank you for always being there for me and taking care of me. You are the best sister a girl could ask for. Happy Anniversary!
13. Happy 18th wedding anniversary! I wish that all of your dreams come true. From birthdays to holidays, I’m wishing you happiness and laughter every day. You are the best sister in the world and I love you forever.
14. Congratulations on reaching your 18th wedding anniversary! Loving you has been a true blessing and I am so glad to be your sister.
15. There is a song that comes on the radio, you turn it up and then you giggle at each other when it’s over. You hold hands walking through the park as if you have known each other forever. There is no love quite like the love of sisters, and there is no sister quite like mine. Happy 18th anniversary!
16. May the years to come be filled with happiness and laughter. You have been a wonderful sister to me and I will always cherish our relationship. Thank you for being so special to me, and may you have an anniversary you will always remember! Happy 18th wedding anniversary sister!
17. Here’s to 18 years of love, laughter, and tickling instead of fighting! For 18 years of being the best sister I could ever ask for. May we always be there for each other, no matter how far apart we are.
18. Mary, you are my sister and always will be. We have shared many fun times together and I will never forget that. Happy anniversary. I hope it is the best one yet! Love you, Jenny.
19. Today I am more grateful than ever that our parents brought us together. You’ve made my life so much better and are an amazing friend, sister, lover and partner. Everyday I thank god for you and the plans he had when he put us together. Happy Anniversary My Love!
20. I love my big sister! You have always been there for me for anything I needed. You are a wonderful woman and I am so glad I got to grow up and spend my life with you. I wish you all the happiness in the world, sister dear ~
21. Dear sister, I am so glad we have each other. You are the best sister a girl could ask for. We have been through so much together and I couldn’t image life without you. Speaking of, remember when we were kids?! How about that time in high school when you tripped me and I fell into the mud?! Oh my gosh, I still get so embarrassed thinking about that! But who else could laugh at me like you do? Sister, you are one of kind. Happy 18th wedding anniversary sister!
22. You are the whole world to me. I don’t say it as much as I should but I know every time we talk that you are in my heart, always. It is so special to have you by my side and I am so lucky to have your love. You inspire me with your kindness and the way you live your life. Happy 18th wedding anniversary sister!
23. We both had worn out dreams of what our life would be like when we were finally wed…and it turned out to be so much more. We always talk about how lucky we are that our journey together has led us to all that we have today. You have been by my side for the last 18 years, and it feels like I have known you forever. I’ll never forget the day that we became one. I will be forever thankful to God for you! Happy 18th wedding anniversary sister!
24. Sis, I remember the first day I met you at the airport. You were so excited to be going on a trip and I just knew that you would be a fun person to travel with. We have travelled all over together and have seen some amazing sites. So much has happened in the last 18 years, and our friendship is still as strong as ever. I love you so much! Happy 18th anniversary. Love always, your brother-in-law
25. Happy anniversary to my sister of 18 years, my partner for life. I want to thank you for staying with me these past 18 years and making me a better person. Nothing means more to me than knowing you will always be by my side.
26. It’s hard to believe that as Chris and I celebrate our 1st wedding anniversary you will be getting married. You are the sister every girl dreams of having. You are kind, creative, and truly the most loving person I know. I am so happy that you found your soul mate and have allowed me to join in on your special day! Congratulations on the upcoming big step in your life! Happy 18th wedding anniversary sister!
27. It’s hard to believe that it’s been a whole 18 years since you and your husband have been married. You are the most amazing example of love and marriage in this family.  You are truly a blessing and I am so glad you are part of our family. Happy Anniversary! Love, ___________
28. You are not just my sister, best friend and shoulder to lean on, but also the woman who brought me into this world. 18 years ago you told me we were sisters and moments later I met mom. 18 years ago, you left your family to move hundreds of miles away and start a new one with me. I really don’t know how I could survive one day without you. You are truly everything to me and always have been. You have been there through thick and thin,
29. Happy Anniversary. I love you and have loved every single moment we have shared. You make my life complete, you are my best friend and the love of my life. I am so lucky to have you in my life, happy anniversary and I love you!
30. I’ve been your sister all my life, but you have been my best friend since the day I was born. I love that we can always be completely real and honest with each other. You have taught me so much about myself and the world at large. You have supported me when I needed it, and you have been a constant source of joy, adventure and laughter in my life. What an incredible bond we share! You’re one of the most amazing people I know.
31. Happy anniversary. We have come a long way together but most of all we have become better people because of it. I thank God every day for leading me to you and allowing us to share such a great love. I couldn’t have waked down this path without your support, love and guidance through it all. Check out: 17th Wedding Anniversary Wishes For Sister
32. Words above all else. That’s how I want to always treat you. Words above all else. That’s what it means to me to be a part of this family. Happy anniversary!
33. I pray that you and Paul are blessed with as many happy years together as possible. I’m grateful for the opportunity to celebrate with you; hopefully next year we’ll be raising a glass on your 18th anniversary!
34. Sis, Happy 18th anniversary! Just because I’m not in the bridal party doesn’t mean we are not celebrating this one together. We have been through it all and have all the memories to prove it! You are the best sister a girl could ask for and my favorite partner in crime. Thank you for everything every day.
35. You’re my best friend and I love that you have been there through all the highs and lows of life. I can’t wait to celebrate your 18th wedding anniversary with you as a sister as well as a friend! While men may come and go, our friendship is here to stay.
36. I can’t believe you’re getting married on Saturday! We have been together through so much. From your first date with Steve to your engagement, weddings and now babies. You have grown up into such a strong, smart and beautiful woman. I am so proud to be your big sister. Your happiness means the world to me and I can’t wait to see you walk down that aisle! Congratulations!

Also See: 19th Wedding Anniversary Wishes For Sister