Spirits are not something I personally believe in, however - if they were real then I wouldn’t have thought they would affect you for making a tarot deck. Especially as a deck is not just filled with what we perceive as negative cards but also positive ones too which provide an overall balance.

It’s more than likely that your mother is troubled by something else in her subconscious that she doesn’t realise.. or she has picked up a ‘spirit’ from outside the home if that is something you believe in.

I know you said about your energy being poured into the deck but you’re making this for a relative so I imagine there is a lot more of love and caring there then anything else because it’s a gift.

My interpretation of tarot is normally a very generic one though in the sense that it can help open your mind and look at situations from a different perspective etc.