SyntaxError: positional argument follows keyword argument

Try this:

dbc.Col(
    html.Div(
        id='myid',
        children=[
            html.P('text'),
            html.H4('text2'),
            html.P("text3"),
            html.H4('text4')
        ],
    ),
    width={'size':1,'offset':1}
)

I believe children= is optional IF it is the 1st argument.