Run script in back ground

I have a script "a" running in background. From script "a" i will kick off script "b" which will also be in background. Is this possible. And actually what i want is, In script "b" when i do ps -ef, script "a" should not be seen.

Current "a" script

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---
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nohup b
exit

current 'B' script

sleep 160
ps -ef
--
---
exit

In B when i do ps -ef,i should not see "a" script running. Is this possible

to put b in bg just call
./b &
but everybody will see your scripts in the process list using ps -ef. imposible to hide a process from anyone