Are undocumented immigrants really to blame for rising prices under Trump?

My mom is a big trump supporter and he can do no wrong in her eyes. My dad used to be a big trump supporter but he's not very happy with him, because he campaigned on lowering gas prices and groceries on day one, but they actually increased. I don't know how he was stupid enough to believe that, but I told my mom that, and she was like "well, its because of the illegal aliens" I asked her to clarify, and she was like "because they are getting everything for free, so we all have to pay more, and that makes prices go up". I asked, "so if republicans have the house, the senate, and presidency, then why are there still illegals getting in, and in turn raising prices?" She was like "they are here because of Bidens policies" I then asked then why did prices go up as soon as trump took office" she just kept saying that it is bidens fault with no explanation" I was so frustrated and disappointed in my moms stupidity, I almost just jumped out of the car. My dad was very similar, but he seems to be breaking free. Anyone else know trump supporters like this?

Are undocumented immigrants really to blame for rising prices under Trump?
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