I know any type of infection , especially a UTI can bring on sudden confusion or worsening behaviour, but how can I tell (at this stage) if Mums is just due to being overwhelmed with family birthdays, Christmas etc Mum has already said to me twice that "Christmas" is too much for her brain. Mum has already lost concept of time, days, weeks, dates etc Now even the date December 25th means nothing to her really. It is my sisters & Dads birthdays today which she did remember to buy cards, ( although she got Dad a "Happy Birthday Father" ) but when at my sisters for lunch she said that no one told her it was Christmas. Angry that we were all going to my sisters for Christmas dinner, that she hadn't been invited, and that she never gets invited anywhere for Christmas dinner, and we always leave her out. On going home, my sister was putting things in the boot of her car, which is a range rover style where the boot is like a door that opens out, and Mum went to climb in the boot Just seems like bizarre behaviour, and sudden confusion about Christmas and all the family traditions.