Thank you, Eldercat, Greenport ferals and Spirite!
I think Sophie is about 3-4 months old. I am yet to take her to the vet to get her spayed and shots, etc. They'll be able to give us the exact age.
This cat tree is very nice and it's been used a lot. Had to repair it several times, but I am looking into something more narrow and tall now to save space. Will keep this one too for a while or the cats may get upset if it's gone. It sure saved our furniture lol.