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Attempting to locate further children and extended families etc.
Some records have surname as Lalor/Lawler
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Still looking through the Electoral rolls for 1939 and am at a loss as to where I should look further
Unfortunately there's no simple way to search forward, since the online parish records tend to finish up by 1900, sometimes earlier. You would have to take a chance and order possible civil certs based purely on likely names and location, to check for births of other children, or their later marriages.
From the late 1920s the online version of the index includes mother's maiden name, which can help the search for births, particularly with a relativity uncommon maiden name like Watters, although possibly a little too late for this couple. The index books in the GRO research room in Dublin contain the maiden name from about 1904.
Shane