show image in loop get term

I use under Code
How can show image in src=”” .help my.please!

                        $term_children = get_terms(
                            'category-product',
                            array(
                                'parent' => get_queried_object_id(),
                            )
                        );

                        if ( ! is_wp_error( $terms ) ) {
                            echo '<div class="row">';
                            foreach ( $term_children as $child ) {
                                echo '
                                    <div class="col-md-4 col-sm-6 col-xs-12">
                                        <div class="item-product">
                                            <div class="item">
                                                <div class="image">
                                                    <a href="' . get_term_link( $child ) . '"><img alt="' . $child->name . '" src="" class="img-fluid"></a>
                                                </div>
                                                <div class="text-wrapp">
                                                    <h3><a href="' . get_term_link( $child ) . '">' . $child->name . '</a></h3>
                                                </div>
                                            </div>
                                        </div>
                                    </div>
                                ';
                            }
                            echo '</div>';
                        }