To not pay their air fare

Id personally say you have to be accountable for the money in their accounts for care home fees
As a one off you'd be happy to help cover the cousins airfare but not her DH (after all your father will like to see cousin but not her husband). But it will be the last time you can cover it... id also wait for them to ask you for the money.

Paying for flights for your cousins and her family would be considered as deprivation of assets and therefore would need to be included when eventually the second parent dies.

Deprivation of assets doesn’t apply to IHT. The form for it looks at assets and debts at time of death and significant gifts made from capital in the preceding seven years. You’re muddying the waters with irrelevance.

What do they do when the come? Treat it like a holiday and sightsee, go on day trips etc, or just spend time with your parents? The latter I would be more inclined to help out. If they pop in to see parents briefly they use you as a base for holidaying then no.

I think you should pay none of it. You need to keep that money for your parents care, if it runs out you will be the one paying the care home bills

As you’re saying they have enough money to pay for a combined 16 years worth of care, which at what could be upwards of £50K annually, they are likely to have £800k in savings. Plus the value of the house which I’m guessing hasn’t been sold as you say you want to inherit it? If those assumptions are correct then you’re in Inheritance Tax territory. Paying for flights for your cousins and her family would be considered as deprivation of assets and therefore would need to be included when eventually the second parent dies.
Honestly, I’d get your DPs a decent iPad and let your cousin FaceTime them instead. They don’t want to really see their aunt and uncle, they just want a free holiday.

PoA means you’re responsible for using money in the way its owner would if they still had capacity. Obviously the owner of the money has set a precedent over many years which you should follow @rookiemere. It’s quite unbelievable that you take money for your son but are contemplating going against what have been your dad’s clear wishes.

Because it’s not their money, they have a duty to use their parents money in accordance with their last known wishes which is that DF has funded his family to visit for many years. Whether they agree with his wishes, it’s not their money to preserve for their own benefit/inheritance.

If it brings your DP's pleasure, then do it. But make sure that you are crystal clear about what is being paid for and what they need for pay for themselves. That way there isn't any confusion when they're here.

I would not mention it. Cheeky buggers though if they do ask for two people with dementia in a care home to pay for their holidays!

But since they are coming now, wouldn't this be the best time to set expectations now ie that money now has to be prioritised for care and the option of annual visits might need to be self funded in the future. I'd prefer to deal with this head on not let it hang over OP @rookiemere till next year.

This is a nasty and absurd reply.

OP’s parents set up a payment to their grandson. OP is continuing this. She is making a contribution to her cousin’s flights.

Sorry but in the real world direct descendants, eg daughter and grandson, take precedence over nieces and their family.

Also re the money for your son you are potentially storing up IHT problems if they are not from excess income. This article gives an overview as a starting point https://www.thp.co.uk/gifts-out-of-surplus-income/

Whilst it might have been out of excess income and therefore exempt while they were living at home this may not be the case now covering two sets of care home fees

For somebody with dementia your DF seems to have capacity so it’s his decision not yours.

I don’t know anyone who has actually been challenged on it, but it’s a direct quote from the gov website about being an poa:
—-
Spending money on gifts or donations
Unless the LPA states otherwise, you can spend money on:

• gifts to a donor’s friend, family member or acquaintance on occasions when you would normally give gifts (such as birthdays or anniversaries)
• donations to a charity that the donor would not object to, for example a charity they’ve donated to before

• paying someone’s school or university fees
• letting someone live in the donor’s property without paying market rent (anything they pay below market rent counts as a gift)
• interest-free loans

The husband has also coped with the impact of OP caring for her parents so he's accepted losses to his own family life from that. Why should OP and her spouse expected to not think of their own immediate family's wellbeing at all, but cheerfully fund trips for more distant relatives?

If it brings your df some joy then I absolutely would

If you do contribute then I think you need to make it clear that this will be the last time it happens.

That would also then apply to her own DCs allowance - what’s sauce for the goose and all that.

Or she could suck up her annoyance, accept her parents last known wishes and support her dad to see his family.

I think that is something that may have changed in the last 10 or so years. I know when I did POA for an aunt, the guidance I received with the POA said was no gifts. When my aunt’s cousin died we did send a donation from my aunt to the charity chosen for the memorial collection but I was prepared to refund this money if it had been questioned. I took the view that my aunt would have wanted to send this.

This 👍
My parents tbh loved the thought of visits but it exhausted them, anything more than 5 mins of small talk was too much. My parents especially my dad preferred few mins facetime a week not 30 min visits. The conversation usually went 'hello binkie, lovely to see you, hope you're fine, catch you next week' about 30 seconds. Occasionally it would be an hour of him telling me about the snooker, golf or tennis. The point being he didn't physically need me in the room just the company.
I think just airfare this year is fine, definitely would not facilitate by having them stay. You and the care home can organise facetiming your dad. Seeing someone's face and smile is the joy. I wonder if cousin sends regular gifts and cards or is the interest only once a year to coincide with a holiday.

I think as his loved niece and with a clear precedent then sending a contribution to help with airfare to visit for her would survive legal scrutiny.

She's asked for B&B recommendations. That will turn into quite a cost forcing them to eat out for every lunch and dinner so she may be assuming she will be welcome at yours.
I would send links only to places which are near to the care home and/or suggest an alternative if the care home is close to a train station for example.

What would? Continuing to fund the visits? Or stopping?

I actually don’t have specific advice because I don’t understand the legal requirements - if it was me I’d be looking for advise from a solicitor or govt agency.

However, I do think OP’s actions are being driven by her personal feelings about her cousin (or the husband) rather than a concern for the legal requirements, or financial factors. Thinking through whether you’d be comfortable with the decision if you had to explain it to your parents I think is a good exercise to get to your motives.

I do have concern if the goal is to protect her inheritance rather than protect her parents financial future. Or just avoid someone they don’t like.

I think you should cover it but say its the last time you can pay....if they ask.

I think you've made a typo in an earlier post which is confusing a lot of people (including me) in which you say your DF thinks you should not mention it and see if they ask. From later posts, it's clear that was your DH, but that might have been missed.

You need to come on more often then as most of us regulars are fluent in MN now and read acronyms as pure English 😂