Susan Sarandon

Susan Sarandon

Susan Sarandon's granddaughter will have an "unusual" name.

The 'Stepmom' actress' daughter Eva Amurri Martino and her husband Kyle are set to welcome their first child into the world in August, and the brunette beauty admits they've already chosen a moniker for the unborn tot.

Speaking to PEOPLE, she said: "It's not a vegetable, a city or a place. It's a real name, but it's unusual. I really like it."

The 67-year-old star - who also has sons Jack, 24, and Miles, 21, with ex-partner Tim Robbins, as well as Eva, whose father is filmmaker Franco Amurri - is looking forward to meeting the little one when she's born and insists she'll be on hand to help change her dirty nappies.

She explained: "I'm very excited to be a grandmother. It's going to happen soon. She's due in August. I'm making my way to LA and cleared August and most of September to be with her."

Asked whether she'd be changing nappies, she added: "I changed all of my kids nappies. It's different when it's your granddaughter though. I'm going to follow all my daughter's rules, but behind her back I'm going to break them and spoil the baby because I think that's what grandmothers are for."

Meanwhile, Susan has already decided that she wants the youngster to call her Honey rather than grandma.

She explained: "It [Honey] seems different and sounds warm and sweet. I don't know if the baby will know how to say it right away, but that's what we are going for."