Q’s on double insurance coverage

Before you jump to telling me not to get double insurance coverage…I have some questions.

My partner’s job currently offers us United Health Care – we are in the high deductible plan with an HSA that we need. I am starting a new job this week and they also offer United Health Care with a benny card (and a low deductible/no monthly premiums out of my own pocket).

1) Would it be possible for me to enroll in my new employer’s plan as well and get double coverage from United Health Care, under two separate policies? I’ve asked a million questions of their reps by phone and they never know the answer, so here I am. It seems weird to me but not impossible. Definitely a logistical headache with billing when they confuse the details.

The logic is that because the deductible is so, so low for my job ($500), the benny card they are offering is worth it ($5K annually). We keep my partner’s plan because we receive an HSA and part of that money is invested, so it is pretty sizeable for emergencies.

2) Am i required to add our child to my work’s health insurance? I can only find online that children generally receive the coverage from the parent whose birthday comes first in the calendar year, but at my last job (when I also had double insurance), they automatically added him and said it was his primary. Never fought it since it was 100% paid by my employer and had no co-pays.