Inheritance tax on joint accounts

I’m claiming my mother as a dependent and filing as head of household as I have the last few years.  She passed away in 2025 but I’ve confirmed I can still claim her as dependent on my 2025 taxes.   I have a question about inheritance tax.

She didn’t have a will and had 2 assets.  A checking account containing about $23,000 at the time of death.  In addition to her name, my name was also on the account.   I never contributed to it nor did I take money out for myself.  But my name was listed on the account.  My name was actually listed first.  Do I have to pay an inheritance tax due to me ‘inheriting’ her half?   For Turbo Tax purposes, would this be categorized as an inheritance? 

Similarly, she also had about $2,600 in a credit union account.  My name was also listed on this account.   I’m assuming I also need to claim her half of this as an inheritance.  I did receive a letter after her death from the PA Dept. of Revenue (Pennsylvania is where my mother and I resided) indicating that the credit union notified PA that since I was a joint owner of my mom’s account, I had to pay PA a 4.5% tax on half the amount.  I’ve since sent PA a check and paid that tax. Interestingly, I never received any notification from the Federal Government about this.  I would think since the credit union notified the PA Dept of Revenue, they would have notified the Federal Government too.  I assume I still need to list this as an inheritance on the Federal return.  Is that true?