A makeup artist-turned-yoga instructor, Doria lives in Los Angeles, where she raised Meghan, Duchess of Sussex.
Now, the 62-year-old is by Meghan's side as she navigates motherhood for the first time.
"Like all mums, Doria wants to be there for her daughter at this seismic event in her life," a source told The Sun.
"She has sometimes worried about being so far away but she is absolutely going to be there for her at the birth."
By rocky, we are referring to Meg's extended family and own father, Thomas Markle, who has continuously slammed his daughter and also begged for her forgiveness throughout her sudden rise into the British royal family.
"For me to watch this level of lifelong sensitivity to nurturing and care-giving, but at the same time my mum has always been a free spirit," Meghan has said of Baby Sussex's lesser known grandmother.
"She's got dreadlocks and a nose ring. She just ran the LA Marathon. We can just have so much fun together, and yet, I'll still find so much solace in her support."
Doria is also responsible for her "Flower" Meghan's insatiable love for charity work - something she and Harry share.
"I must have been about 10 years old when we visited the slums of Jamaica," Meghan explained on her past blog The Tig.
"I had never seen poverty at that level and it registered in my glazed brown eyes. 'Don't look scared, Flower,"'" she said. "'Be aware, but don't be afraid.'"
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