Safari in macOS ignore no children processes memory info

In macOS tracking Safari main pid seems not to take care of children processes memory info

macOS BigSur 11.5.1)
Safari 14.1.2
Python 3.7.3

EXAMPLE taken with this command:
sudo psrecord 39720 --log process.txt --include-children --interval 2
while opening a lot of new tabs

# Elapsed time CPU (%) Real (MB) Virtual (MB)
0.000 0.000 230.277 6517.668
2.017 5.400 230.344 6518.219
4.044 15.000 230.465 6518.336
6.061 42.900 230.922 6519.691
8.090 55.600 231.098 6521.992
10.105 40.700 231.828 6521.992
12.137 17.000 231.730 6520.469
14.161 81.300 232.609 6521.070
16.189 61.600 232.980 6521.328
18.221 31.200 231.961 6520.262

Start by reproducing the reported `sudo psrecord 39720 --log process.txt --include-children --interval 2` command on macOS with Safari while opening several tabs. Trace how `--include-children` gathers process memory, then verify that the output accounts for Safari's child processes rather than only the main PID.

Written by the indexing model from the issue text.