Here is a nice selection of family-friendly events for this weekend:
Colour! in The Ark - 15th July - 23rd August (Wednesday - Sunday)
http://http://ark.ie/events/view/colour
Summer in Dublin in Henry street - 25th July - 28rd August (Saturday)
http://www.dublintown.ie/whats-on-events/summer-dublin-events
Dublin Castle Sand Sculpture Exhibition - 3rd - 25th August
https://www.facebook.com/permalink.php?story_fbid=1028189160525781&id=621875627823805
Drop-in Family Workshop in the National Gallery of Ireland - 8th August
http://www.nationalgallery.ie/whatson/Summer_2015/Family_workshop/Aug8_family.aspx
Friends of Breastfeeding Summer Picnic - 8th August
https://www.facebook.com/events/1655838504649923/
Dun Laoghaire Intertidal Ecology - 8th August
http://events.dlrcoco.ie/event/biodiversity-events
Caribbean Jerk Festival in Fairview Park - 8th August
https://www.facebook.com/events/1414717105519165/
Outdoor Movies in Marley Park - 8th & 9th August
http://www.dlrevents.ie/movies15.html
Drop-in Activity in Collins Barracks - 9th August
http://www.museum.ie/en/list/calendar-of-events.aspx?eventID=4709
Fusion Sunday World Culture Market in Dublin 8 - 9th August
https://www.facebook.com/events/428380597345383/