I didn't even know it was possible to do that! But today I got an offer from the science center to turn my imaginary friend "real", if I found them a rainbow stone so they could make a potion. My question is, what kind of stone in this? Can I find it out and about, is there a specific place or event that has to trigger it?

I turned aging off because I was horrified the IF would disappear when she became a teen, and I want to transform it before it's too late. So, I need help: how do I find the stone? Can I make the potion myself on the chemistry set?

Yes, you can find the gem... I know you can find it in Sunset Valley, here are some places where it usually is. It's pretty rare. You could also find it from using a miner (from Ambitions) or just putting a rainbow gem spawner from the buydebug section of the catalog onto your lot

I don't know a whole lot about the chemistry table but I've heard that's the other way to make your imaginary friend real.

Just had this happen today. My sim's child had an imaginary friend; his father discovered the potion that makes the I.F. real, so I put it in the child's inventory. I immediately got (when switching back to the child) the option to make him real.

Using the Chemistry set is probably the best way. Rainbow Gems are rare, and the potion itself is 4500 simoleons. So if you can, try to find it using the chemistry set. Cheaper overall, and more fun if you ask me

I agree with laceyharkness - I've done it both ways with IFs, once via the gem and once with the chemistry set. The gem is a PITA to find and it took several sim days to find one. The chemistry set was much moar funner.

If you want to find the stone it respawns in very few locations - there are three maybe four, but I can only remember two! One is round the back of the criminal warehouse in SV, near the cherrytree, it can spawn either inside or outside the fence. Or across the road from Agnes Crumplebottom's house and the three vacant lots next to her house there is a lamp-post and a rock, the gem can spawn between the rock and the lamp--post. The third one is on the way to the waterfall but I can't quite remember where ..

I use a custom world and just can't find the rainbow gem. I have my sim's partner spending all his spare time on the chemistry table. Hopefully he will get the potion soon.

I must be having a glitch; my kid has the potion and has spent about 20 days sucking up to his doll so far, and there has been no options, and no ways to cram the potion down that doll's throat.

There are several ways for you to get it.

If you're a martial artist, one of the achievements allows you to get random gems when you break the space rocks.

If you're an inventor, you can build a Digger and get rocks randomly as well.

If you're a traveler, you can try your luck on the vacation destinations.

Lastly, you can also check out the consignment store everyday.

Don't worry the IF doesn't disappear when the child becomes a teen or even an adult. And you can make it real any of those times.