My sister-in-law offered us her used car seat, which is a pretty nice brand (Britax). I know she can be a little rough on things and this car seat has been through numerous trips to the mountains, checked on the airplane, and dozens of car rides. The last time I saw this car seat, I was sitting next to her 1.5 year old son when he threw up all over it (yes, I know my baby will throw up too!). However, I cannot bear the thought of using this car seat for my first brand new baby. When my husband politely turned it down, she seemed extremely offended... Now I feel awful and I'm not sure what to say when I see her next. Suggestions?