Two dozen brownies is 2 * 12 = <<2*12=24>>24 brownies.
After Father ate his 8, there were 24 - 8 = <<24-8=16>>16 brownies remaining on the counter.
After Mooney ate her 4, there were 16 - 4 = <<16-4=12>>12 brownies remaining on the counter.
Mother made a second batch of two-dozen brownies, or 2 * 12 = <<2*12=24>>24 brownies.
After Mother added the second two-dozen, there were 12 + 24 = <<12+24=36>>36 brownies on the kitchen counter.
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