We've got thousands of toys that we kept from when DS1 was a baby and can't think of anything that we really need for DS2 that we haven't already got. We'll get him clothes and pj's but i really don't want more toys.
Just tell DS1 that Santa likes to recycle old toys. Get him to pack up all his baby toys in a box and leave them for Santa's helpers to collect a few weeks before christmas, then Santa brings them back for DS2.
That seems very sensible. We did this when our children were small. We never had a problem with the other children thinking that FC had forgotten the baby. This was because we always told them that FC only bought the stocking presants eveything else was from us and othet people.