You can collect data on descendant processes subject to some limitations.
If you want to collect data for all descendant processes that are followed by the Collector, you must use the collect command with the one of the following options:
-F on option enables you to collect data automatically for calls to fork and its variants and exec and its variants.
-F all option causes the Collector to follow all descendant processes, including those due to calls to system, popen, and sh.
-F '=regexp' option enables data to be collected on all descendant processes whose name or lineage matches the specified regular expression.
See Experiment Control Options for more information about the -F option.