Here you go — about 45 seconds:

> Hi everyone, I'm [your name], [sister's name]'s [brother/sister], and I couldn't be prouder to be standing here today.
>
> I've always admired my sister's determination. If you've ever seen her on a climbing wall, you'll know — she doesn't give up easily. She works through the problem, commits, and goes for it.
>
> So it feels very fitting that she met Elliot at the climbing gym. Elliot, from the start you've matched her energy, supported her, and made her incredibly happy. Welcome to the family.
>
> Sis, I love you, and I'm so excited for everything ahead of you both.
>
> Please raise a glass — to my sister and Elliot, and to a lifetime of adventure together. Cheers!