Hen trying to encourage another hen to go broody?

[HenHangout]

I have a Brahma hen that has never went broody, but has helped with parenting previous batches of chicks.

Today I saw that Brahma get into a nesting box occupied by my youngest silkie hen, and push eggs under the silkie. Is this something hens do to encourage other hens to brood? Should I try adding more eggs to that particular nesting box?

 

[oldhenlikesdogs]

I see the Brahma pushing the eggs under herself. All hens will do this if there's eggs in a nest. They also prefer to lay where another hen has laid. Why not have another hen hatch and raise your chicks?