Most recently, they arrived home with two Father's Day cards, spoiling the effect a little by insisting one of them was for their mother. And while, in common with many parents, we already have an extensive collection of hand-prints around the house, applied with a range of materials from yoghurt to indelible ink, the cards were always touching.
I didn't take the day off work for my daughter's graduation, because I thought that might be overdoing it. But then, of course, I got delayed and missed the start of the ceremony. Fortunately, she didn't seem to notice, and anyway, I was there for the important part. When they called her name and she walked forward to receive her scroll, I was ready with the camera; although not so ready that I didn't have to ask her to give the scroll back and receive it again - slowly, this time.
It was a proud moment for any parent, as you can imagine. But, as always on these occasions, it was also tinged with sadness. It seemed like only yesterday that Roisin was a baby.
Now, incredibly, she was nearly four. And here she was at the crèche, receiving a certificate to the effect that she had completed Montessori classes and was graduating to - I'm quoting from the citation - "big school".
As usual, the crèche pulled out all the stops for the ceremony. Admittedly, it was a slight disappointment that the citations weren't in Latin. But otherwise the occasion had all the solemnity you could risk with children, some still young enough to want to eat their certificates.
Of course it wasn't all solemn. The part I missed included a communal poetry reading by the Montessori graduates, which luckily my wife recorded. I watched it alone later that night, and I'm not exaggerating when I say there wasn't a dry eye in the house.
The thing is, there was added poignancy to the event for us. As the class of 2002 mingled excitedly and discussed plans, we were aware that, for both our children, this was the last day at the crèche. My wife has decided to take a break from the workforce and, in defiance of Government policy, enter the parent force full-time. This is a big move. And while its full consequences are lost on Patrick, aged two-and-a-half, we were a little worried about how his sister would react.
Even four-year-olds have a limited grasp of concepts, such as "the past" and "the future". But for the umpteenth time, after the ceremony, I reminded Roisin that she wouldn't be coming here anymore. With the tone of voice you use to explain that Santa Claus has left the North Pole and is on his way, I said: "From now on, Mammy will be staying at home with you."
But as we watched her playing run and catch in the yard (Roisin, that is, not her mother) for the last time, we were the ones finding it hard to let go.
The new arrangement is a little daunting. Although sending two children to a crèche in Dublin is more expensive than owning a house (unless it's a much bigger house than ours), there are major benefits. A good crèche offers a standard of service that parents - most of them having entered parenthood without a recognised childcare qualification - can find hard to replicate.
Also, despite the chaos they create, children love order. They need you to provide them with structures, until they're old enough to reject everything you and Western civilisation stand for. But order doesn't come easily. Fortunately, the crèche was organised like an army camp, with fixed dinner time, play time, nap time, etc, and the children brought some of this home. In periods of crisis (evenings or weekends, when the crèche was closed) you could sometimes buy a few minutes peace by drawing the curtains and announcing in a confident voice that it was "quiet time!"
Another thing we'll miss about the crèche is that it never allowed an occasion to go uncelebrated. Even the Hallmark Card Company is not as enthusiastic about marking special occasions as the crèche was. Whether it was Christmas or St Patrick's Day or Easter, the kids were guaranteed to come home with greeting cards made during arts-and-crafts time - usually involving hand prints in paint.
But parenting is like a book. You close one exciting chapter, and you open another (only to discover that the kids have torn the next five pages out). So with crèche-style sense of occasion last week, we finally announced that it was "goodbye time".
And in a flurry of hugs and kisses, Roisin and Patrick threw themselves into the ceremony with enthusiasm. No doubt thinking this was a new part of the daily routine, and that tomorrow they'd be saying goodbye to the crèche all over again.
