Melanie Jane Smith is due to appear before magistrates in Prestatyn on Tuesday morning in connection with a house fire in Prestatyn.
The 42-year-old was charged with four counts of murder, one count of arson with intent to endanger life and threats to commit criminal damage yesterday.
Lee-Anna Shiers died in the fire along with her niece and nephew Bailey and Skye Allen. 15-month-old Charlie Timbrell died from burns suffered in the fire at Liverpool's Alder Hay Hospital.
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