I am going to have watch more closely.

My father is 87. He is alert, mentally active and as physically active as someone with two knee and two shoulder joint replacements can expect to be...but the last 24 hours have suggested that I need to watch more closely. He let the kettle boil almost dry (I rescued it when I came home in time), failed to put the 'phone properly back on the hook, and left the garden hose running overnight. He is not sleeping as well as he usually does.
His mind is elsewhere at the moment. I know what the problem is and I cannot do a damn thing about it. My youngest sister has been living elsewhere for the past nine and a half years. This has been a great relief to everyone. She has made the sudden decision to return 'home'.
She will not be living with us but she will be much closer than she was - too close.
My father loves her as parents do love their children but he does not want her living close by. She worries him.
My other siblings and I are, with good cause, deeply concerned by her decision. We also wonder why she has made this decision. We wonder whether the claims to have work where she was living are true and whether any of a host of other statements she has made to our father in recent years are true. It is unlikely they all are true. We know that. My father wants to believe them. It is the only way he can cope with her erratic behaviour, unreliability and lack of sense of responsibility.
She believes that they are 'good mates' so that arriving late or not at all or asking for money is not an issue. None of her problems are ever her fault and she is a very convincing liar. We could all cope with her more easily if she was mentally ill. She is not. She is a sibling.