求助 Python multiprocessing 守护进程为什么不允许有子进程？

本人代码如下：

import multiprocessing
import time

def process_a():
for _ in range(10):
print("process a")
time.sleep(1)

def process_b():
print("process b")
ps = []
for _ in range(3):
p = multiprocessing.Process(target=process_a)
p.daemon = True
p.start()
ps.append(p)
for i in ps:
i.join()

if __name__ == '__main__':
p = multiprocessing.Process(target=process_b)
p.daemon = True
p.start()
p.join()

运行报错：AssertionError: daemonic processes are not allowed to have children
想问一下 multiprocessing 是出于什么原因，决定守护进程不能再创建子进程？谢谢