These ponies came in a 3-pack creatively titled “Pretty Ponies”.
In 2023, this style of pony was released as “Pretty Pony Surprise” with one of the ponies being hidden in the packaging:
The adult is approx. 5″ tall, marked RMS International on the hoof:
The babies (one unicorn and one earth pony per set) are 4″ tall with no hoof markings:
The brush, I believe, is a copy of an Equestria Girls design:
These 3 were sold individually at Five Below in summer 2024. They are the 4″ size.