Teresa Palmer will be a bridesmaid at her husband's ex-partner's wedding.

Teresa Palmer

Teresa Palmer

The 30-year-old model-and-actress - who is expecting her second child with husband Mark Webber - is very "proud" of Frankie Shaw and can't wait to be by her side when she walks down the aisle is a few months.

The 'Point Break' star shared a picture of herself and Frankie hugging and posted: "So proud of this lady! This is (Aunty) Frankie @frankieshawisag my stepson Isaac's Mama (We share @likemark as our babies dada!).

"She is also my friend and in two weeks I'll be a bridesmaid in her wedding."

Teresa is pleased she and Frankie - who split from Mark a few months after their son Isaac, now eight, was born - have such an "amazing" relationship despite traditional expectations of how it should be.

The actress - who has two-year-old son Bodhi with Mark -wrote: "We rewrote how society sees what our relationship should look like and it feels really amazing.

"She [Frankie] directed me in her amazing short film #Toolegit, this is us today at #Sundance #NEXTfest where her film screened, we got ready together. @yourzenmama #family #leadwithlove #coparents (sic)."

Frankie, 29, also praised her pal as being a great mother.

She reposted the picture and gushed: "#nextfest premiere of #toolegit with @teresapalmer. damn, you're such a good mom sometimes I wish it was me in your belly (sic)."

Teresa was quick to respond and commented on the photo: "Awe love you so much!!!! (sic)."