“I think that she provides such a wonderful environment for Matilda to grow up in, especially in the sort of industry that she’s in,” Heath’s sister Kate Ledger tells PEOPLE for this week’s cover story in advance of the upcoming Spike TV documentary I Am Heath Ledger, which is set to premiere on Spike TV on May 17 following its debut at the Tribeca Film Festival on April 23. (The documentary will also have a special one-night theatrical release on May 3.)
Matilda was only 2 years old when Ledger, 28, died of an accidental overdose inside his Manhattan apartment on Jan. 22, 2008. Although Williams has said “it just won’t ever be right” for Matilda to grow up without her dad, his friends and family praise the Manchester by the Sea star for her strength as a mom.
“The way she’s been an incredible mother, she has hero status all across the board,” says Ledger’s close friend Matt Amato, with whom he co-founded the music and film company The Masses.
Kate Ledger praises Michelle as “really grounded and down to earth,” and says the similarities between her niece and her late brother are striking.
“When [Matilda] picks up her pencil, it reminds me of Heath; when she walks, it reminds me of Heath; when she gets on her skateboard, it reminds me of Heath,” she says. “I tell her about her daddy every time we see each other. I tell her little stories of him growing up and how he used to chase me with the cricket bat.”
This story originally appeared on PEOPLE.com.