The `Hold It Against Me` singer - who has been married twice before - has told friends she wants her partner of two years to propose by the end of the year as she wants a normal family life for her and her two sons, Sean Preston, five, and four-year-old Jayden James.
A source said: "After all her ups and downs Brit is craving stability - hence her broodiness at the moment - and she just wants to settle down with Jason and do it all again the right way.
"Now her album is out and her tour is almost sorted she feels like getting married again and having more children is the next step."
Britney - who split from husband Kevin Federline in 2006 after two years of marriage, while her union with childhood friend Jason Alexander was annulled in January 2004 - recently spoke about agent Jason, saying how she loves how normal and grounded their life is together.
She said: "We`re really normal. We just like to watch movies. We work out a lot. We love to work out. We do stuff together like that. We take walks."