Toilet seat for D Shape toilet with removable kids' seat.
This has worked great for our elder son through toddler years, and he still uses it at age 4.5.
Has to go quickly, as we're moving.
I also am offering a similar family toilet seat for a regular elongated bowl toilet but haven't had a chance to photograph it yet.
Family D Shape toilet seat (NW3 Swiss Cottage)
This offer has been gifted to someone and is no longer available.