No grass? Well, I'm sorry to say this, but that's not good. It's like trying to raise a vegetarian cat.I don't have any grass, but I did just start a fodder system so in about 5 days I should have some wheat sprouts for her!
She does get to go outside whenever I'm outside, but now that school has started back up that will be only a couple times during the week and on Saturdays. The rest of the time she is inside with us. The rest of the family likes her and all, but she is MY pet and so is MY responsibility so no one else is willing to take her out to play, they just let her run around the house trying to eat the dogs long ear fur =P
Geese primarily eat grass. A few wheat sprouts won't get you anywhere. Aside from that, she needs the sunlight to develop an adequate amount of vitamin D. If you want to keep her as a pet, you need to let her graze outside for several hours every day.
Please reconsider your arrangements for Trina.