Jessica Simpson at the San Diego Airport, June 1. [Agencies]

Jessica Simpson is convinced her sister Ashlee Simpson-Wentz will make a great parent - because she "inspires love" in those around her.

Singer Ashlee Simpson - who wed rocker Pete Wentz last month - finally confirmed she is expecting her first child with the Fall Out Boy star last Thursday.

And 27-year-old Jessica has no doubt her younger sibling, 23, will take to parenthood with ease.

She tells People.com, "She'll be amazing, absolutely amazing."

"They're just the cutest couple in the world. They are adorable. Anybody would wish to be them and you can only wish them well. Just being around them inspires love and everything I sing about."