Ashlee Simpson was ''nervous'' meeting her boyfriend's mother, Diana Ross.

The legendary Supremes singer's son, Evan Ross, introduced her to his famous girlfriend at Los Angeles' Aventine Trattoria bar on Saturday night (03.08.13), where the star was celebrating with family members after performing at the Hollywood Bowl, and Ashlee was said to be anxious about their first encounter.

Despite her nerves, Ashlee - who has a four-year-old son, Bronx, with ex-husband Pete Wentz - was warmly received by Diana, 69, who was described as ''wonderful and very open'', according to the New York Post newspaper.

The 28-year-old actress-and-singer and Evan, 24, were smitten with each other at the family occasion as they were spotted ''dancing and kissing'' the night away, and it seems the former 'Melrose Place' star fit in well with her boyfriend's relatives.

A source added to ''She was nice and said hello to Diana. Everyone was in a good mood and Ashlee just blended in as Diana's son's girlfriend.''

Ashlee appears to be getting serious with Evan, who she has been dating since June, and they even were overheard discussing a romantic getaway together.

An onlooker said: ''Ashlee was talking about travelling soon with Evan. They were very affectionate.''

The couple got together after Ashlee split from 'Boardwalk Empire' actor Vincent Piazza in November.