Two baby showers...? Advice

Is anyone else having two baby showers?...I work in a school like environment and my best friend (who I work with) wanted to throw me a baby shower but so did my mom and sister in law. At first, I counted everyone up and it was well around 200-250 people that would end up being invited (family and close friends ONLY). We came up with the idea to split the baby shower in half. Have my mom and SIL throw one and invite family and close family friends and have my best friend throw one with all my work friends and families. The problem I'm faced with is there's a lot of people that fall in the area of both...they're really good friends that I work with that I consider family but I feel that if I invite them to both they'll feel obligated to buy me something for both showers which I want to avoid. I don't want to seem rude and not invite them to the family one that my mom and SIL are throwing but I don't want to make them feel like they need to go and get me something. We've already considered combining the two and that idea kept being shot down. It's out of my control. These are also people that would buy me a big gift both times regardless of me telling them not to. I just don't want to seem like the rude ungrateful one that's inviting people to both showers to get things out of them because that's not the case, but I don't want them to feel left out either. Can anyone help me out please