Should I accept the money or should I decline the money politely?

My sister in law gave us a hand me down crib that is about 8 years old. I was excited at first because it would save us a huge expense. Then I found out it had a recalled part and we were having some issues with the drop side sticking. After reading the dangers of older cribs, I told my sister in law about the recall and we are going to purchase a new one that is rated high on CPSC and was only $150 at walmart (we did a lot of research). I told her it probably would be fine, but it was mostly a piece of mind thing for replacing the crib. She said she certainly understood. At our last baby shower, she and her husband gave us a check for $150. She had told my husband that she felt bad about the crib not working out. They had already given us several hand me down clothes and went in on buying our new infant car seat, stroller and car seat base, so I never in a million years felt they should give us anything to replace the crib. Now I am not sure how to handle the check. Should I call her and tell her how much I appreciate it but never felt that they should give us anything for the crib or just accept the money?