The individual portrait is quieter by contrast and all eyes are on the individual.
The other aspect to this decision is how the painting will move through the family generations. Individual portraits can easily be passed on to the next generation.
One exciting option these days is that one can have a giclee made of the original painting and have that framed and given to the other siblings or all the siblings while the parents own the original.
I find that most families have a sense of what is best for their family and do not labor unduly over this decision.
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Sonia Hale is an award-winning, nationally-collected artist in Boston. She paints commissioned portraits for families and institutions nationwide. Her original landscape and still life oil paintings can be purchased at http://www.soniahale.com. For more information, go to http://www.soniahale.com. You can reach her by email at soniahale1@gmail.com.