Observation-level random effects

No, they are not the replicates of the same family, but 20 different
families under Cross (Population) Farm.NA.

Dear Shahin. 
Thierry has already answered your question, in that unless you provide a within-family standard deviation for each 
"development.overall" or "egg.size" observation, there is no information about familial random effects. You can examine paternal 
and maternal contributions, since some of these are repeated across families (in your example data), 
but you will not have a lot of power, I fear.