There is nothing worse than losing a child. Only, there might be. Surely, there can be nothing worse than losing a child at the hands of someone else.

The sheer guilt that they should have been with you, the what-ifs and the if-onlys, the not daring to imagine what they’ve been through or are still going through.

It is a parent’s worst nightmare  – a horrific, unimaginable scenario that no one would want visited upon them.

Kate and Gerry McCann and Coral and Paul Jones are living with that horror each and every day.

For Coral and Paul, it is a distress that will never leave. Their little five-year-old girl was snatched by alcoholic paedophile Mark Bridger, a man they thought they knew; the man who killed their daughter and steadfastly refuses to say where her remains are.

Coral says she cannot even have the peace of laying her daughter properly to rest because all she got back of her were a few bones.

For Kate and Gerry, the where? why? how? who? the what-ifs and the if-onlys go on and on and on.

On Wednesday night I was with Coral, Paul, Kate and Gerry, hosting a fundraising dinner for the charity Missing People.

Both mums are passionate that a Child Rescue Alert system becomes a routine part of procedure when a child goes missing. It alerts the public to an abduction, as soon as possible, preferably in the first vital few hours after a child disappears, which are crucial to the success of finding the child before they’re harmed.

When Madeleine was taken from her room in Portugal seven years ago, Kate says she took it for granted that such an alert would have been put out on the day her little girl disappeared. It wasn’t.

Coral, still very nervous, and emotional, but determined to make her precious April’s death count for something, spoke about how she never wants what happened to her family to happen to anyone else’s as she – almost finding it hard to breathe at times – appealed for funds for an enhanced Child Rescue Alert in the UK.

The alert works when a child goes missing and is thought to be in clear or imminent danger. Police, after assessing the case, have to give permission for it to be used and if they agree that it warrants an immediate alert, Missing People presses the button and messages go out to broadcasters, press, social media and to people who’ve signed up to receive the service.

It’s already in ­operation in Ireland, Greece, ­Netherlands and the US, among others, where over two thirds of children are found.

Meanwhile, Kate McCann lives with eternal hope, but for Coral Jones the only hope is that another child’s life will be saved so the agony of the loss of her ­treasured April might not be in vain.

You can sign up to receive Child Rescue Alerts at childrescuealert.org.uk. It would make Coral’s day.