Here are some ideas for what to say for a 25th birthday:

• "Happy 25th birthday! I hope you have a beautiful day and make yourself happy by offering yourself some small gifts. Lots of love! Take care of yourself."
• "You’re 25. Feeling unsure and lost is part of your path. Don’t avoid it. See what those feelings are showing you and use it."
• "Happy 25th birthday! May your day be filled with love, beauty, and friendship."
• "25, young, and fabulous."
• "Many congratulations and many happy returns on your 25th birthday! I hope that a lot of happiness awaits you in the years to come and that you are presented with many exciting opportunities."

When deciding what to say, consider the personality of the birthday person, the message you want to convey, and the tone of your relationship with them. You can also add humor, compliments, and heartfelt messages to make the birthday wish more personal and memorable.