Small Creatures Stabs People With Ring and They Turn To Giant Seeds

by Mandy
(Mesa, Arizona)

I saw a movie in the early 90's when I was around eight-ten and it scared me horribly, and I'd like to see it again now but I can't remember the name.

Here's what I remember:

1) There are two children, a young girl (under ten) is main character.

2) The girl likes to bounce a ball and sing the 'Peas Porridge Hot' song in the basement.

3) There's a small child-sized creature with a ring and a needle coming out of it. He stabs people with it and they turn into giant seeds.

5) In the end, there's an apartment filled with plants.

Please help me remember what this movie is. Thanks!