How We Met: Ronni Ancona & Eva Rice

'She walked into my antenatal class, and I thought, "Oh, it's Nigella!"'

Ronnie (left) says of Eva: 'I didn't know her family background initially as we never talked about surnames. It wasn't until I saw a photo of [her father] Tim Rice on her wall that I thought, gosh she looks a bit like him.' (Anna Huix)

Eva Rice, 37

The daughter of lyricist Tim, Rice (right in picture) embarked on a career as a singer-songwriter – but it was her debut novel, 'Standing Room Only', that propelled her into the public eye. Her third book, 'The Lost Art of Keeping Secrets', sold more than a quarter of a million copies. She lives in Notting Hill with her husband.

I'd seen Ronni on Alistair McGowan's Big Impression and particularly liked her Posh Spice routine. And then she walked into my antenatal class six weeks before our first babies were due, and I did a double-take; I thought, "Oh, it's Nigella; oh, it's Posh Spice…" We all sat around for our first session with dolls to put nappies on, and we were both total idiots with no clue what to do.

I know her primarily as the mother of Lily. That's our focus: the school, the girls, who's going round to who's. Having kids fast-tracked our friendship, because for that first child it's really important to be with people you can have a laugh with. I remember sitting in a café with my baby and feeling someone had just given me a live toy I didn't know how to operate. Then I looked at Ronni and realised we both felt we were in the same boat, and that was a comforting feeling.

She's a good actress – she has that way of soaking up people's personas and the way they talk. But as a comedian she is atypical; she is unbelievably beautiful and in comedy that works against you. In Skins she played a teenager's mother, but what was funny was how most teenage boys in the cast fancied her anyway.

I use Ronni as my comedienne gimp. At our Christmas party for the other mums at my house she read The Night Before Christmas in three voices, including Marilyn Monroe. And at our party to celebrate the Royal Wedding, she impersonated every guest walking into the church – she even did the Queen.

Having her still-born son in 2006 was tough for her. It's one reason I wanted her to be godmother to Kit, my second son. She still talks about her little boy – it's how she deals with it; she often asks me what it's like having a boy that age.

Both of her girls have inherited her sense of the dramatic. If one of her kids is having a full-scale meltdown she'll say, "Oh my god it's Lana Turner again"; she's great at finding comedy in difficult moments of parenthood.

Ronni Ancona, 44

Best known for her myriad impressions, Ancona has also carved out a career as an actress, most recently appearing in TV drama 'The Last Tango in Halifax'. She lives in west London with her husband and two children.

I met Eva at my antenatal class, in a café up Portobello Road in London. We bonded immediately as we were the naughty ones at the back, sniggering every time the word "vagina" was mentioned. You can tell you're kindred souls when you can be rude to one another so early on.

Then I had my little girl and we went through this incredibly challenging, knackering time of early motherhood together. It turns your world upside down and those around you are dragged into it. I'd turn up with my hair sticking up on end, congealed yoghurt down my top and my breasts on the floor and Eva would be like, "You look great!".

I didn't know her family background initially as we never talked about surnames. It wasn't until I saw a photo of [her father] Tim Rice on her wall that I thought, gosh she looks a bit like him. I saw him recently at Eva's and I said to him, "Tim, you've got such talented children – where do they get it from?" He laughed at that – the man's a legend. Eva's working on a musical now, too, and the songs are truly beautiful.

Shortly after I found out about her family connections I got invited to her book launch, for The Lost Art of Keeping Secrets. When I read it I was like, oh good, she's not only beautiful and adorable, but talented too. She's got an agelessness to her writing. She has a great manner of speaking, too, as she uses her hands to gesticulate a lot of vocabulary marks; she's always doing parentheses in the air.

Every year Eva and [her husband, the musician] Pete [Hobbs] do a Christmas soirée; they pick up a guitar and do some songs together. Then there's me with my appalling recorder-playing. I'm hopeless; all I do is stupid voices.

I was the first to get pregnant with a boy, then Eva had a little boy, Billy. But I lost mine. For a while it was hard for her knowing how to [approach my loss], but she was incredibly supportive and we became closer for it.

When we meet up these days, Eva is a total lightweight when it comes to wine – she has two sips and says, "That's gone right to my head." I like a few glasses so I'm like, "For God's sake!" I've just played an alcoholic in Last Tango in Halifax, but I don't want to come across as an alcoholic!

Rice's new novel, 'The Misinterpretation of Tara Jupp' (Heron Books, £14.99), is out on Thursday