You made it through the toddler stage!And now you've got an extra day tagged on to the child stage? UGH. The last thing we need is extra days. The boys are very cute, though.
I didn't know that rocket science was added as a mentorable skill. I know that with fishing a Sim that doesn't have level 10 can sometimes mentor. In one of my tournament practice runs, Bjorn Bjergsen was able to mentor my my Level 0 Sim, even though I think Bjorn starts out at Level 3. I haven't tested that to any real degree, but once my Sim reached Level 4 Bjorn couldn't mentor her. So, Erwin may or may not have Level 10 Rocket Science Skill. The only way to know for sure is to invite him back over when Vicente has Level 9 and see if Erwin can still mentor. For the purposes of the challenge, I agree that it's best to make rocket science a shared skill since you can't definitively say whether Erwin has maxed it.
Too bad about the garden. Unfortunately, it's probably going to take a week (give or take) before your plants are green again if you're playing 28 day seasons. I hate the brown plants, too. So ugly!