Bell Beaker blogger has an interesting post summarizing new evidence regarding the burial practices of Europeans in areas where the Bell Beaker culture appeared.
In a nutshell, immediately before the Beaker era, children were buried (as was everyone) in undistinguished collective graves.
In the early Beaker period, there was a sharp divide between non-Beaker child burials which omitted all children under six months of age, involved collective child graves, and had no grave goods, and contemporaneous child burials of Beaker people, in which all children were buried with adults who seemed to be their parents or relatives and grave goods were present. The Beaker children were better fed with lots of milk and meat, and people buried in Beaker graves had longer lives, on average, than those buried in non-Beaker graves.
Later in the Beaker period, all graves followed a Bell Beaker-like pattern, and individuals and adults were each buried in separate graves.
This tends to show that there was a Beaker superstrate which was culturally distinct from the substrate people in the same time and place, and that life was better for Beaker people, not in small part due to their ability to include meat and milk in their diets which the autochronous people lacked.