I'm struggling with this right now. The one gift (compared to 8 they sent for DD) my parents sent DS for Easter is a gigantic, loud, plastic, battery-hogging ball thing. After I told them we gave him a kid-powered, metal (and some plastic) ball run for Christmas. There are so many issues involved I can't even list them all!
Anyway, since we do not celebrate Easter, and knowing my parents, I set them aside and pre-opened them today without the kids. Most of DDs are... acceptable until they break and we trash them. I guess they thought we'd let DS open his immediately since he just had one, so we couldn't let each open one immediately and set the rest aside (as they know we usually do with big gift piles.)
I will be returning it. I will not be telling them I took it back, because I don't feel like fighting with them. If they ask, I will just say "oh, it doesn't get a lot of use here, it's so big and requires so many batteries" when they ask how he likes it. I mean, the goals with such a gift are 1) Annoy me. (I grew up with them; this is absolutely what they intend.) 2) Take over our 540 square foot home with large plastic junk because they cannot stand non-cluttered spaces (seriously, the hoarding is really really bad at all my direct relatives houses). 3) Buy love with junk. 4) establish that DD is their favored and he is not; 5) Perhaps entertain DS.
I will, though, feel that I need to replace it with something for DS because there are so many gifts for DD. It was her birthday a few weeks ago though, so it may just become "late birthday presents" for her instead. Then it's just the issue that eventually DS will notice that they send him nothing for his birthday (literally, they gave him no first birthday present) and dozens for DDs birthday--6 or so for her birthday and now 8 more "Easter" ones. That I haven't figured out what to do yet.